Abstract: The next generation of health care professionals need to understand the foundational principles of biology. While science textbooks play a critical role in supporting biological understanding, they are often written 3 to 5 years beyond their intended grade level. Additionally, many students read 2-3 years below grade level, making a gap of 8 grade levels possible between what a student can read and what he or she is assigned. From a cognitive learning perspective, the syntactic and semantic complexities of science texts often overwhelm students? working memory, preventing them from constructing the accurate mental representations that would allow them to learn new biology or science content. SquidBooks seeks to address the limitations of current textbooks and revolutionize reading with adaptable texts. Like the shape-shifting form of a squid at sea, SquidBooks change on demand to meet the needs of diverse readers. Transforming the learning process, SquidBooks makes texts flexible by offering books at different reading levels with embedded language support to create a personalized reading experience, which optimizes learning and engagement. The proposed Phase I project will use the SquidBooks concept to develop a new web-based technology: an interactive, digital textbook comprehensively addressing the life science concept of inheritance, one of 42 disciplinary core ideas in the Next Generation Science Standards (NGSS). The overall goal of the Phase I project is to positively impact students? understanding of biology, which will serve as the Phase I milestone. The program will involve the creation of subject content for inheritance that will include images, videos, and diagrams (Aim 1). This content will then be used to construct a prototype of the digital textbook that will function through a web browser (Aim 2). The prototype will undergo user testing with students and teachers to assess the efficacy of SquidBooks to improve science learning outcomes utilizing a counterbalanced repeated measure, within subject design (Aim 3). The trial will also involve feedback from these participants about the usability and feasibility of the interactive, digital textbook. The successful completion of the proposed project will (a) create knowledge about disciplinary textual processing and adaptive reading technologies for the field of education, and (b) support scientific literacy, especially among students with reading difficulties or low English reading skills, enhancing and diversifying the STEM and health care fields.